Wireless Access

Our enterprise is transitioning several locations from Cisco wireless to Aruba and I recieved a request for a deployment at a site with existing Cisco CAPWAP APs. Because of their close proximity, only one additional access point should be sufficient to cover the new area. My initial inclination was to go with deploying a Cisco AP to accomodate for redundancy and seamless roaming in the same mobility domain (then later we can upgrade all the APs on the floor to Aruba). I have been advised by the design team to go ahead a deploy an Aruba AP and join it to our new controllers because the same VLAN will be used with an identical SSID, and thusly because of that, roaming should work fine without the end-devices dropping connection or having to re-authenticate (we use PEAP with MSCHAP).

From a Cisco standpoint, I was under the impression that roaming between controllers that are not in the same mobility domain is impossible, even if the same VLAN/subnet is being used on both. Is that not the case in this scenario as well?

You can roam between Aruba and Cisco if the clients are placed on the same VLAN and have the same default gateway.  At issue is that Cisco broadcasts a QBSS load element that Cisco phones and Cisco supplicants will find more attractive than Aruba Access points that do not broadcast this.

What you can do is to enable the "Advertise QBSS Load IE" option in the advanced parameters of the Aruba SSID profile and you will make this more even.

Hi Colin,

That is an interesting piece of information, thank you.  Is this only applicable to Cisco phones and PC's with the Cisco supplicant, i.e. would vanilla Windows 7 PC's or iPhones need any special tweaking to get them to roam successfully between Cisco and Aruba ?

Thanks

UPDATE:

Since this posting, it has been advised to avoid multi-vendor roaming at all costs due to how difficult it can be to normalize client behavior.  Conversions should be done to entire buildings or floors to avoid roaming between vendors as much as possible.

Hello!

With the recent aquisition of HP (Aruba), the company caused a big problem for their customers. I have a big infraestructure in my company: We have about 350 Access Points HP MSM in the same site (very near each one) and about 150 more in other sites. We have recents projects with this equipaments and we can't replace now (obviously). Even if we wanted, is impossible to change the HP MSM Access Points for Aruba, because this means unavailability for our internal customers and a complex project of migration no need.

We had some meetings with our account manager, but until now we don't have a solution for this.

Will impossible to scale (grow up) our network now, because we can't install one Access Point Aruba near of one Access Point HP MSM. The roaming between these Access Points is not transparent for the clients. Ex.: If some user have a active session with some application and he to move for other WiFi cell, with one diferent Access Point, certainly he'll have a problem. The end of sales of MSM is near.

In our case, this situation will be very common, because we have several Access Points spread by the Site.

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@cjoseph wrote:

UPDATE:

 

Since this posting, it has been advised to avoid multi-vendor roaming at all costs due to how difficult it can be to normalize client behavior.  Conversions should be done to entire buildings or floors to avoid roaming between vendors as much as possible.

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How can we solve this problem?

I certainly think you should speak to your account manager and his/her engineer to determine where you go from here.  They know your system and they should be able to present some sort of solution to you.